This is the Windows Store app. Or, at least it would be if it worked. For now, it's just a splash screen...
Well, if would still be a splash screen if it wasn't for the fact that after a long wait, an error message appears.
The one I got first was:
We weren't able to connect to the Store. This might have happened because of a server problem or the network connection might have timed out. Please wait a few minutes and try again. (0x80072ee2)
The next attempt in opening the store app resulted in another error:
We weren't able to connect to the Store. This might have happened because of a server problem or the network connection might have timed out. Please wait a few minutes and try again. (0x80190190)
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Note how, in both cases, the error code was different...
So if you're currently encountering an error message with the same error codes, then you're in luck, since there is a fix! If the error code and problem is similar (but not exactly the same) then in any case just have a read through and see if your problem gets fixed.